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1.
Phys Chem Chem Phys ; 26(3): 2341-2354, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38165967

RESUMEN

Polarization, as an important characterization of the symmetry breaking systems, has attracted tremendous attention in two-dimensional (2D) materials. Due to their significant symmetry breaking, Janus 2D ferrovalley materials provide a desirable platform to investigate the charge, spin, and valley polarization, as well as their coupling effects. Herein, using first-principles calculations, the polarization properties of charge, spin, and valley in Janus VSiGeZ4 (Z = N, P, and As) monolayers are systematically studied. The mirror symmetry breaking leads to a non-zero dipole moment and surface work function difference, indicating the presence of out-of-plane charge polarization. Magnetic properties calculations demonstrate that VSiGeN4 is a 2D-XY magnet with a Berezinskii-Kosterlitz-Thouless temperature of 342 K, while VSiGeP4 and VSiGeAs4 have an out-of-plane magnetization with a Curie temperature below room temperature. The magnetization can be rotated by applying biaxial strain, allowing manipulation of the spin polarization via nonmagnetic means. The spontaneous valley polarization is predicted to be 46, 49, and 70 meV for VSiGeN4, VSiGeP4, and VSiGeAs4, respectively, whose physical origin can be elucidated by employing the model analysis. In particular, the biaxial strain can induce the valley polarization switching from the valence (conduction) band to conduction (valence) band, but it hardly changes the valley polarization strength. Meanwhile, the valley extremum is transformed from the K' (K) to K (K') points. The present work not only provides an underlying insight into the polarization properties of Janus VSiGeZ4 but also offers a class of promising materials for spintronic and valleytronic devices.

2.
Appl Microbiol Biotechnol ; 108(1): 300, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619710

RESUMEN

The gut microbiota (GM) and its potential functions play a crucial role in maintaining host health and longevity. The aim of this study was to investigate the potential relationship between GM and longevity. We collected fecal samples from 92 healthy volunteers (middle-aged and elderly: 43-79 years old; longevity: ≥ 90 years old) from Changshou Town, Zhongxiang City, Hubei, China. In addition, we collected samples from 30 healthy middle-aged and elderly controls (aged 51-70 years) from Wuhan, Hubei. The 16S rDNA V3 + V4 region of the fecal samples was sequenced using high-throughput sequencing technology. Diversity analysis results showed that the elderly group with longevity and the elderly group with low body mass index (BMI) exhibited higher α diversity. However, no significant difference was observed in ß diversity. The results of the microbiome composition indicate that Firmicutes, Proteobacteria, and Bacteroidota are the core phyla in all groups. Compared to younger elderly individuals, Akkermansia and Lactobacillus are significantly enriched in the long-lived elderly group, while Megamonas is significantly reduced. In addition, a high abundance of Akkermansia is a significant characteristic of elderly populations with low BMI values. Furthermore, the functional prediction results showed that the elderly longevity group had higher abilities in short-chain fatty acid metabolism, amino acid metabolism, and xenobiotic biodegradation. Taken together, our study provides characteristic information on GM in the long-lived elderly population in Changshou Town. This study can serve as a valuable addition to the current research on age-related GM. KEY POINTS: • The gut microbiota of elderly individuals with longevity and low BMI exhibit higher alpha diversity • Gut microbiota diversity did not differ significantly between genders in the elderly population • Several potentially beneficial bacteria (e.g., Akkermansia and Lactobacillus) are enriched in long-lived individuals.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Persona de Mediana Edad , Humanos , Anciano , Femenino , Masculino , Adulto , Anciano de 80 o más Años , China , Akkermansia , Bacteroidetes , Lactobacillus
3.
Sensors (Basel) ; 24(8)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38676220

RESUMEN

Long-term coherent integration (CI) can effectively improve the radar detection capability for high-speed targets. However, the range walk (RW) effect caused by high-speed motion significantly degrades the detection performance. To improve detection performance, this study proposes an improved algorithm based on the modified Radon inverse Fourier transform (denoted as IMRIFT). The proposed algorithm uses parameter searching for velocity estimation, designs a compensation function based on the relationship between velocity and distance walk and Doppler ambiguity terms, and performs CI based on the compensated signal. IMRIFT can achieve RW correction, avoid the blind-speed sidelobe (BSSL) effect caused by velocity mismatch, and improve detection performance, while ensuring low computational complexity. In addition, considering the relationship between energy concentration regions and bandwidth in the 2D frequency domain, a fast method based on IMIRFT is proposed, which can balance computational cost and detection capacity. Finally, a series of comparative experiments are conducted to demonstrate the effectiveness of the proposed algorithm and the fast method.

4.
Molecules ; 29(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38792181

RESUMEN

This study investigates the utilisation of organometallic network frameworks composed of fourth-period transition metals and tetrahydroxyquinone (THQ) in electrocatalytic CO2 reduction. Density functional theory (DFT) calculations were employed in analysing binding energies, as well as the stabilities of metal atoms within the THQ frameworks, for transition metal TM-THQs ranging from Y to Cd. The findings demonstrate how metal atoms could be effectively dispersed and held within the THQ frameworks due to sufficiently high binding energies. Most TM-THQ frameworks exhibited favourable selectivity towards CO2 reduction, except for Tc and Ru, which experienced competition from hydrogen evolution reaction (HER) and required solution environments with pH values greater than 5.716 and 8.819, respectively, to exhibit CO2RR selectivity. Notably, the primary product of Y, Ag, and Cd was HCOOH; Mo produced HCHO; Pd yielded CO; and Zr, Nb, Tc, Ru, and Rh predominantly generated CH4. Among the studied frameworks, Zr-THQ displayed values of 1.212 V and 1.043 V, corresponding to the highest limiting potential and overpotential, respectively, while other metal-organic frameworks displayed relatively low ranges of overpotentials from 0.179 V to 0.949 V. Consequently, it is predicted that the TM-THQ framework constructed using a fourth-period transition metal and tetrahydroxyquinone exhibits robust electrocatalytic reduction of CO2 catalytic activity.

5.
Molecules ; 29(12)2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38930961

RESUMEN

Metal-organic frameworks have demonstrated great capacity in catalytic CO2 reduction due to their versatile pore structures, diverse active sites, and functionalization capabilities. In this study, a novel electrocatalytic framework for CO2 reduction was designed and implemented using 2D coordination network-type transition metal-hexahydroxytricyclic quinazoline (TM-HHTQ) materials. Density functional theory calculations were carried out to examine the binding energies between the HHTQ substrate and 10 single TM atoms, ranging from Sc to Zn, which revealed a stable distribution of metal atoms on the HHTQ substrate. The majority of the catalysts exhibited high selectivity for CO2 reduction, except for the Mn-HHTQ catalysts, which only exhibited selectivity at pH values above 4.183. Specifically, Ti and Cr primarily produced HCOOH, with corresponding 0.606 V and 0.236 V overpotentials. Vanadium produced CH4 as the main product with an overpotential of 0.675 V, while Fe formed HCHO with an overpotential of 0.342 V. Therefore, V, Cr, Fe, and Ti exhibit promising potential as electrocatalysts for carbon dioxide reduction due to their favorable product selectivity and low overpotential. Cu mainly produces CH3OH as the primary product, with an overpotential of 0.96 V. Zn primarily produces CO with a relatively high overpotential of 1.046 V. In contrast, catalysts such as Sc, Mn, Ni, and Co, among others, produce multiple products simultaneously at the same rate-limiting step and potential threshold.

6.
Metab Eng ; 80: 66-77, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37709005

RESUMEN

Chinese hamster ovary (CHO) cells are the preferred mammalian host cells for therapeutic protein production that have been extensively engineered to possess the desired attributes for high-yield protein production. However, empirical approaches for identifying novel engineering targets are laborious and time-consuming. Here, we established a genome-wide CRISPR/Cas9 screening platform for CHO-K1 cells with 111,651 guide RNAs (gRNAs) targeting 21,585 genes using a virus-free recombinase-mediated cassette exchange-based gRNA integration method. Using this platform, we performed a positive selection screening under hyperosmotic stress conditions and identified 180 genes whose perturbations conferred resistance to hyperosmotic stress in CHO cells. Functional enrichment analysis identified hyperosmotic stress responsive gene clusters, such as tRNA wobble uridine modification and signaling pathways associated with cell cycle arrest. Furthermore, we validated 32 top-scoring candidates and observed a high rate of hit confirmation, demonstrating the potential of the screening platform. Knockout of the novel target genes, Zfr and Pnp, in monoclonal antibody (mAb)-producing recombinant CHO (rCHO) cells and bispecific antibody (bsAb)-producing rCHO cells enhanced their resistance to hyperosmotic stress, thereby improving mAb and bsAb production. Overall, the collective findings demonstrate the value of the screening platform as a powerful tool to investigate the functions of genes associated with hyperosmotic stress and to discover novel targets for rational cell engineering on a genome-wide scale in CHO cells.


Asunto(s)
Sistemas CRISPR-Cas , ARN Guía de Sistemas CRISPR-Cas , Cricetinae , Animales , Cricetulus , Células CHO , Genoma , Anticuerpos Monoclonales
7.
Int J Colorectal Dis ; 38(1): 212, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37566134

RESUMEN

OBJECTIVE: To evaluate the effects of glutamine on the plasma protein and inflammatory responses in colorectal cancer (CRC) patients following radical surgery. METHODS: We thoroughly retrieved online databases (EMBASE, MEDLINE, PubMed, and others) and selected the randomized controlled trials (RCTs) with glutamine vs. conventional nutrition or blank treatment up until March 2023. The plasma protein associated markers indicators (consisting of albumin (ALB), prealbumin (PA), nitrogen balance (NB), total protein (TP)), inflammatory indicators (including TNF-α, CRP, infectious complications (ICs)), and matching 95% confidence intervals (CIs) were evaluated utilizing the pooled analysis. Subsequently, meta-regression analysis, contour-enhanced funnel plot, Egger's test, and sensitivity analysis were carried out. RESULTS: We discovered 26 RCTs, included an aggregate of 1678 patients, out of which 844 were classified into the glutamine group whereas 834 were classified into the control group. The findings recorded from pooled analysis illustrated that glutamine substantially enhanced the plasma protein markers (ALB [SMD[random-effect] = 0.79, 95% CI: 0.55 to 1.03, I2 = 79.4%], PA [SMD[random-effect] = 0.94, 95% CI: 0.69 to 1.20, I2 = 75.1%], NB [SMD[random-effect] = 1.11, 95% CI: 0.46 to 1.75, I2 = 86.9%). However, the content of TP was subjected to comparison across the 2 groups, and no statistical significance was found (SMD[random-effect] = - 0.02, 95% CI: - 0.60 to 0.57, P = 0.959, I2 = 89.7%). Meanwhile, the inflammatory indicators (including TNF-α [SMD[random-effect] = - 1.86, 95% CI: - 2.21 to - 1.59, I2 = 56.7%], CRP [SMD[random-effect] = - 1.94, 95% CI: - 2.41 to - 1.48, I2 = 79.9%], ICs [RR[fixed-effect] = 0.31, 95% CI: 0.21 to 0.46, I2 = 0.00%]) were decreased significantly followed by the treatment of glutamine. CONCLUSIONS: The current study's findings illustrated that glutamine was an effective pharmaco-nutrient agent in treating CRC patients following a radical surgical operation. PROSPERO registration number: CRD42021243327.


Asunto(s)
Neoplasias Colorrectales , Glutamina , Humanos , Factor de Necrosis Tumoral alfa , Ensayos Clínicos Controlados Aleatorios como Asunto , Inflamación , Albúminas , Neoplasias Colorrectales/cirugía
8.
Int J Colorectal Dis ; 38(1): 89, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37004572

RESUMEN

PURPOSE: The standard of care for locally advanced rectal cancer (LARC) has changed from a single radical surgical treatment to the current multimodality treatment (standard chemoradiotherapy (CRT) and total neoadjuvant therapy (TNT)). The efficacy and safety of both TNT and standard CRT are evaluated in randomized controlled trials (RCTs). METHODS: RCTs were comprehensively searched in Chinese and English electronic databases. The experimental and control groups were TNT and the standard CRT, respectively, included in this meta-analysis. The outcomes were assessed through a fixed-effect or random-effect model of pooled odds (OR) or hazard ratios (HR). RESULTS: Eleven RCTs, involving 3,101 patients were included in the final analysis. TNT showed increase in the pathological complete response (pCR) (OR = 1.95, 95% confidence interval (CI): 1.57-2.41; P < 0.05) and the R0 resection (OR = 1.19, 95% CI: 0.99-1.43; P = 0.062). There was no significant difference in local recurrence-free survival (LRFS) (HR = 0.97, P = 0.803), but TNT had better 3-year disease-free survival (DFS) (HR = 0.82, 95% CI: 0.72-0.93, P < 0.05), overall survival (OS) (HR = 0.87, 95% CI: 0.74-1.02, P = 0.08) and distant metastasis-free survival (DMFS) (HR = 0.79, 95% CI: 0.67-0.93, P < 0.05) than standard CRT. CONCLUSIONS: TNT was safe and feasible as it improved pCR and survival outcomes, and reduced the risk of distant metastasis compared with standard CRT. TNT may be a superior strategy for LARC, but more RCTs are needed to prove it. REGISTRATION AND PROTOCOL: PROSPERO CRD42022327697. We added the Chinese database after registration because of the inclusion of fewer RCTs www.crd.york.ac.uk/PROSPERO/ .


Asunto(s)
Neoplasias del Recto , Humanos , Neoplasias del Recto/patología , Terapia Neoadyuvante/efectos adversos , Recto/patología , Supervivencia sin Enfermedad , Quimioradioterapia/efectos adversos , Resultado del Tratamiento , Estadificación de Neoplasias
9.
Phys Chem Chem Phys ; 26(1): 185-197, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38053430

RESUMEN

Two-dimensional materials exhibiting exceptional photocatalytic properties and a low carrier recombination rate have garnered significant attention. However, such attributes are relatively scarce among conventional two-dimensional materials. Two-dimensional Janus materials, owing to their intrinsic electric field, hold substantial promise in the realm of photocatalysis. In this study, we conducted a comprehensive investigation of the electronic, optical and photocatalytic properties, as well as the carrier mobility of SPdAZ2 (A = Si, Ge; Z = N, P, As) monolayers employing first-principles calculations. Employing the HSE06 hybrid density functional, we discovered that all six structures exhibit semiconductor characteristics with indirect band gaps under equilibrium conditions. Notably, SPdSiP2, SPdSiAs2, and SPdGeP2 monolayers displayed advantageous band edge positions, facilitating effective photocatalytic water decomposition. Furthermore, we computed the carrier mobility of SPdAZ2 monolayers, revealing significant variations in the electron and hole mobility along the same direction, which enhances the effective separation of electrons and holes. Finally, we explored the impact of biaxial strain and an applied electric field on the electronic properties, photocatalysis, and light absorption of SPdAZ2 monolayers. These compelling features underscore the broad potential applications of SPdAZ2 (A = Si, Ge; Z = N, P, As) monolayers in the realm of photocatalytic water decomposition.

10.
Phys Chem Chem Phys ; 25(10): 7278-7288, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36810916

RESUMEN

Recently, MA2Z4 materials have received tremendous attention due to their amazing electronic, spintronic, and optoelectronic properties. In this work, we propose a class of 2D Janus materials WSiGeZ4 (Z = N, P, and As). It was found that their electronic and photocatalytic properties are sensitive to the change of the Z element. Biaxial strain results in an indirect-direct band gap transition in WSiGeN4 and a semiconductor-metal transition in WSiGeP4 and WSiGeAs4. Comprehensive studies demonstrate that these transitions as well as valley-contrasting physics are closely related to the crystal field induced orbital distribution. By taking into account several features of the excellent photocatalysts reported for water splitting, we predict three promising photocatalytic materials WSi2N4, WGe2N4, and WSiGeN4. Their optical and photocatalytic properties can be well modulated by applying biaxial strain. Our work not only provides a class of potential electronic and optoelectronic materials but also enriches the study of Janus MA2Z4 materials.

11.
Biochem Genet ; 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38127172

RESUMEN

Sevoflurane is shown to curtail lung cancer (LC) development. Herein, this research sought to investigate the underlying mechanism of sevoflurane in regard to its repressive effects on LC. Expression levels of microRNA (miR)-153-3p, HIF1α, and KDM2B in LC tissues and cells were determined with qRT-PCR. Following sevoflurane pretreatment and/or ectopic expression and knockdown experiments, the malignant phenotypes, and levels of miR-153-3p, HIF1α, and KDM2B in LC A549 cells were detected using Transwell, scratch, EdU, CCK-8, Western blot, and qRT-PCR assays. Relationship between HIF1α and miR-153-3p was verified with a dual-luciferase reporter assay. The interaction between HIF1α and KDM2B was verified with a ChIP assay. LC tissues and cells presented low miR-153-3p expression and high HIF1α and KDM2B expression. Sevoflurane pretreatment, miR-153-3p upregulation, HIF1α downregulation, or KDM2B downregulation impeded the malignant phenotypes of A549 cells. Sevoflurane pretreatment augmented miR-153-3p expression, while miR-153-3p negatively targeted HIF1α. HIF1α bound to the KDM2B promoter to upregulate KDM2B. HIF1α or KDM2B overexpression counteracted the inhibitory effects of sevoflurane pretreatment on A549 cell malignant behaviors. Sevoflurane decreased HIF1α expression through upregulation of miR-153-3p, thereby reducing KDM2B transcription to restrict the malignant phenotypes of LC A549 cells.

12.
J Am Chem Soc ; 144(9): 4091-4101, 2022 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-35171598

RESUMEN

Despite the clinical success of photodynamic therapy (PDT), the application of this medical technique is intrinsically limited by the low oxygen concentrations found in cancer tumors, hampering the production of therapeutically necessary singlet oxygen (1O2). To overcome this limitation, we report on a novel mitochondria-localized iridium(III) endoperoxide prodrug (2-O-IrAn), which, upon two-photon irradiation in NIR, synergistically releases a highly cytotoxic iridium(III) complex (2-IrAn), singlet oxygen, and an alkoxy radical. 2-O-IrAn was found to be highly (photo-)toxic in hypoxic tumor cells and multicellular tumor spheroids (MCTS) in the nanomolar range. To provide cancer selectivity and improve the pharmacological properties of 2-O-IrAn, it was encapsulated into a biotin-functionalized polymer. The generated nanoparticles were found to nearly fully eradicate the tumor inside a mouse model within a single treatment. This study presents, to the best of our knowledge, the first example of an iridium(III)-based endoperoxide prodrug for synergistic photodynamic therapy/photoactivated chemotherapy, opening up new avenues for the treatment of hypoxic tumors.


Asunto(s)
Neoplasias , Fotoquimioterapia , Profármacos , Animales , Línea Celular Tumoral , Hipoxia/tratamiento farmacológico , Iridio/farmacología , Ratones , Mitocondrias , Neoplasias/tratamiento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Profármacos/farmacología , Profármacos/uso terapéutico , Oxígeno Singlete/uso terapéutico
13.
Crit Rev Biotechnol ; 42(5): 651-667, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34612104

RESUMEN

As a committed step in the urea cycle, arginase cleaves l-arginine to form l-ornithine and urea. l-Ornithine is essential to: cell proliferation, collagen formation and other physiological functions, while the urea cycle itself converts highly toxic ammonia to urea for excretion. Recently, arginase was exploited as an efficient catalyst for the environmentally friendly synthesis of l-ornithine, an abundant nonprotein amino acid that is widely employed as a food supplement and nutrition product. It was also proposed as an arginine-reducing agent in order to treat arginase deficiency and to be a means of depleting arginine to treat arginine auxotrophic tumors. Targeting arginase inhibitors of the arginase/ornithine pathway offers great promise as a therapy for: cardiovascular, central nervous system diseases and cancers with high arginase expression. In this review, recent advances in the characteristics, structure, catalytic mechanism and preparation of arginase were summarized, with a focus being placed on the biotechnical and medical applications of arginase. In particular, perspectives have been presented on the challenges and opportunities for the environmentally friendly utilization of arginase during l-ornithine production and in therapies.


Asunto(s)
Arginasa , Ornitina , Aminoácidos/metabolismo , Arginasa/metabolismo , Arginina/metabolismo , Arginina/farmacología , Ornitina/metabolismo , Ornitina/farmacología , Urea/metabolismo
14.
Sensors (Basel) ; 22(18)2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36146339

RESUMEN

An autonomous navigation method based on the fusion of INS (inertial navigation system) measurements with the line-of-sight (LOS) observations of space targets is presented for unmanned aircrafts. INS/GNSS (global navigation satellite system) integration is the conventional approach to achieving the long-term and high-precision navigation of unmanned aircrafts. However, the performance of INS/GNSS integrated navigation may be degraded gradually in a GNSS-denied environment. INS/CNS (celestial navigation system) integrated navigation has been developed as a supplement to the GNSS. A limitation of traditional INS/CNS integrated navigation is that the CNS is not efficient in suppressing the position error of the INS. To solve the abovementioned problems, we studied a novel integrated navigation method, where the position, velocity and attitude errors of the INS were corrected using a star camera mounted on the aircraft in order to observe the space targets whose absolute positions were available. Additionally, a QLEKF (Q-learning extended Kalman filter) is designed for the performance enhancement of the integrated navigation system. The effectiveness of the presented autonomous navigation method based on the star camera and the IMU (inertial measurement unit) is demonstrated via CRLB (Cramer-Rao lower bounds) analysis and numerical simulations.

15.
Angew Chem Int Ed Engl ; 61(33): e202204866, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35736788

RESUMEN

The application of G-quadruplex stabilizers presents a promising anticancer strategy. However, the molecular crowding conditions within cells diminish the potency of current G-quadruplex stabilizers. Herein, chiral RuII -PtII dinuclear complexes were developed as highly potent G-quadruplex stabilizers even under challenging molecular crowding conditions. The compounds were encapsulated with biotin-functionalized DNA cages to enhance sub-cellular localization and provide cancer selectivity. The nanoparticles were able to efficiently inhibit the endogenous activities of telomerase in cisplatin-resistant cancer cells and cause cell death by apoptosis. The nanomaterials demonstrated high antitumor activity towards cisplatin-resistant tumor cells as well as tumor-bearing mice. To the best of our knowledge, this study presents the first example of a RuII -PtII dinuclear complex as a G-quadruplex stabilizer with an anti-cancer effect towards drug-resistant tumors inside an animal model.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , G-Cuádruplex , Neoplasias , Rutenio , Telomerasa , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Cisplatino/metabolismo , Cisplatino/farmacología , Complejos de Coordinación/metabolismo , Complejos de Coordinación/farmacología , Complejos de Coordinación/uso terapéutico , ADN , Ratones , Rutenio/metabolismo , Rutenio/farmacología , Telomerasa/genética , Telómero
16.
Breast Cancer Res Treat ; 190(2): 329-341, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34482483

RESUMEN

PURPOSE: This study aimed to develop and validate a prognostic model for metastasis-free survival (MFS) based on genes that may functionally interact with cytotoxic T lymphocytes (CTLs) and M2 macrophages in patients with triple-negative breast cancer (TNBC) who underwent adjuvant radiotherapy. METHODS: The transcriptional and phenotypic profiles of TNBC and other breast cancer subtypes were downloaded from gene expression omnibus (GEO). The abundance of infiltrated immune cells was evaluated through CIBERSORTx or MCP-counter. A weighted linear model, the score for MFS (SMFS), was developed using the least absolute shrinkage and selection operator (LASSO) in GSE58812 and validated in GSE2034 and GSE12276. The biological implication of the SMFS was explored by evaluating its associations with TNBC molecular subtypes and other radiosensitivity- or immune-related signatures. RESULTS: A model consisting of the PCDH12/ELP3, PCDH12/MSRA, and FAM160B2/MSRA gene expression ratios with non-zero coefficients finally selected by LASSO was developed using GSE58812. In GSE2034 (treatment with adjuvant radiotherapy), the SMFS was significantly associated with MFS in TNBC patients (hazard ratio (HR) = 8.767, 95% confidence interval (CI) 1.856-41.408, P = 0.006) and, to a lesser extent, in non-TNBC patients (HR = 2.888, 95% CI 1.076-7.750, P = 0.035). However, the interaction of subtype (TNBC vs non-TNBC) and the SMFS tended to be significant (Pinteraction = 0.081). In contrast, the SMFS was not significantly associated with MFS in either TNBC patients (P = 0.499) or non-TNBC patients (P = 0.536) in GSE12276 (treatment without radiotherapy). Among the four TNBC molecular subtypes, the c1 and c4 subtypes exhibited higher CTL infiltration and lower SMFS values than the c2 and c3 subtypes. In addition, the SMFS was positively correlated with the abundance of endothelial cells (r = 0.413, P < 0.001). CONCLUSION: The proposed model has the potential to predict MFS in TNBC patients after adjuvant radiotherapy, and the SMFS may represent a measurement of tumor immune suppression.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Células Endoteliales , Humanos , Macrófagos , Pronóstico , Radioterapia Adyuvante , Linfocitos T Citotóxicos , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/terapia
17.
Angew Chem Int Ed Engl ; 60(9): 4657-4665, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33217194

RESUMEN

Immunogenic cell death (ICD) is a vital component of therapeutically induced anti-tumor immunity. An iridium(III) complex (Ir1), containing an N,N-bis(2-chloroethyl)-azane derivate, as an endoplasmic reticulum-localized ICD inducer for non-small cell lung cancer (NSCLC) is reported. The characteristic discharge of damage-associated molecular patterns (DAMPs), that is, cell surface exposure of calreticulin (CRT), extracellular exclusion of high mobility group box 1 (HMGB1), and ATP, were generated by Ir1 in A549 lung cancer cells, accompanied by an increase in endoplasmic reticulum stress and reactive oxygen species (ROS). The vaccination of immunocompetent mice with Ir1-treated dying cells elicited an antitumor CD8+ T cell response and Foxp3+ T cell depletion, which eventually resulted in long-acting anti-tumor immunity by the activation of ICD in lung cancer cells. Ir1 is the first Ir-based complex that is capable of developing an immunomodulatory response by immunogenic cell death.


Asunto(s)
Antineoplásicos/farmacología , Complejos de Coordinación/química , Estrés del Retículo Endoplásmico/efectos de los fármacos , Muerte Celular Inmunogénica/efectos de los fármacos , Iridio/química , Adenosina Trifosfato/metabolismo , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Calreticulina/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Complejos de Coordinación/farmacología , Complejos de Coordinación/uso terapéutico , Retículo Endoplásmico/metabolismo , Femenino , Proteína HMGB1/metabolismo , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno/metabolismo , Tasa de Supervivencia
18.
Biotechnol Bioeng ; 117(2): 593-598, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31631317

RESUMEN

Chinese hamster ovary (CHO) cells are the preferred workhorse for the biopharmaceutical industry, and CRISPR/Cas9 has proven powerful for generating targeted gene perturbations in CHO cells. Here, we expand the CRISPR engineering toolbox with CRISPR activation (CRISPRa) to increase transcription of endogenous genes. We successfully increased transcription of Mgat3 and St6gal1, and verified their activity on a functional level by subsequently detecting that the appropriate glycan structures were produced. This study demonstrates that CRISPRa can make targeted alterations of CHO cells for desired phenotypes.


Asunto(s)
Sistemas CRISPR-Cas/genética , Edición Génica/métodos , Glicosiltransferasas/genética , Animales , Células CHO , Cricetinae , Cricetulus , Glicosilación , Fenotipo , Polisacáridos/análisis , Polisacáridos/química
19.
RNA Biol ; 17(3): 381-394, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31868085

RESUMEN

LncRNA ANCR plays important roles in the modulation of epithelial mesenchymal transition (EMT) and tumour metastasis in many tumours. However, the role of ANCR in regulating hepatocellular carcinoma (HCC) metastasis is still not known. The current study aims to investigate the underlying mechanism for tumour oncogenesis of ANCR in HCC metastasis. HCC cell proliferation and migration/invasion were measured by MTT and Transwell assays. Xenograft model was established to determine the effect of ANCR on HCC growth and metastasis. ChIP assay was used to detect the H3 and H4 histone acetylation levels at the ANCR promoter region. RNA pull-down and RIP assay was performed to analyse the relationship between ANCR and heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1). Dual-luciferase reporter gene assay was conducted to determine the interaction between ANCR and miR-140-3p. The results indicated that ANCR was highly expressed in HCC tissues and cells, which promoted the proliferation and migration/invasion of HCC cells. In vivo experiments showed interfering ANCR suppressed the growth and metastasis of HCC. H3/H4 histone acetylation levels at the ANCR promoter region were elevated in HCC tissues and cells, and interfering histone deacetylases 3 (HDAC3) significantly up-regulated ANCR expression. ANCR could bind to HNRNPA1, and promoted the expression of HNRNPA1 through regulating its degradation. In addition, ANCR upregulated the expression of HNRNPA1 through sponging miR-140-3p. Finally, we found that ANCR promoted the EMT and invasion/migration of HCC cells through regulating HNRNPA1. In conclusion, ANCR promoted HCC metastasis by upregulating HNRNPA1, inhibiting HNRNPA1 degradation and sponging miR-140-3p.


Asunto(s)
Carcinoma Hepatocelular/patología , Ribonucleoproteína Nuclear Heterogénea A1/genética , Neoplasias Hepáticas/patología , ARN Largo no Codificante/genética , Anciano , Animales , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Transición Epitelial-Mesenquimal/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Ribonucleoproteína Nuclear Heterogénea A1/metabolismo , Humanos , Neoplasias Hepáticas/genética , Masculino , Ratones Desnudos , MicroARNs/genética , Persona de Mediana Edad , Estabilidad Proteica , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Angew Chem Int Ed Engl ; 59(8): 3315-3321, 2020 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-31828932

RESUMEN

Reported is the FeIII -activated lysosome-targeting prodrug FerriIridium for gastric cancer theranostics. It contains a meta-imino catechol group that can selectively bond to, and be oxidized by, free FeIII inside the cell. Subsequent oxidative rearrangement releases FeII and hydrolyses the amine bond under acidic conditions, forming an aminobipyridyl Ir complex and 2-hydroxybenzoquinone. Thus, FeII catalyzes the Fenton reaction, transforming hydrogen peroxide into hydroxyl radicals, the benzoquinone compounds interfere with the respiratory chain, and conversion of the prodrug into the Ir complex leads to an increase in phosphorescence and toxicity. These properties, combined with the high FeIII content and acidity of cancer cells, make FerriIridium a selective and efficient theranostic agent (IC50 =9.22 µm for AGS cells vs. >200 µm for LO2 cells). FerriIridium is the first metal-based compound that has been developed for chemotherapy using FeIII to enhance both selectivity and potency.


Asunto(s)
Iridio/química , Hierro/química , Profármacos/química , Neoplasias Gástricas/tratamiento farmacológico , Animales , Humanos , Ratones , Ratones Desnudos , Modelos Moleculares
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